NXP PCF8574 and compatible ICs are simple I2C GPIO expanders.
PCF8574 incorporates quasi-bidirectional IO, and simple
communication protocol, when IO read is I2C byte read, and
IO write is I2C byte write. User can think of it as
open-drain port, when line high state is input and line low
state is output.
Signed-off-by: Dmitrii Sharikhin <d.sharikhin@yadro.com>
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MAINTAINERS | 6 ++
hw/gpio/Kconfig | 4 +
hw/gpio/meson.build | 1 +
hw/gpio/pcf8574.c | 162 ++++++++++++++++++++++++++++++++++++++
include/hw/gpio/pcf8574.h | 15 ++++
5 files changed, 188 insertions(+)
create mode 100644 hw/gpio/pcf8574.c
create mode 100644 include/hw/gpio/pcf8574.h